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        <h2>
          <span class="refentrytitle">median</span>
        </h2>
        <p>median — 
      A median filter, a variant FIR lowpass filter.
    </p>
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      <div class="refsect1">
        <a id="idp123327120"></a>
        <h2>Description</h2>
        <p>
      Implementation of a median filter.
    </p>
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      <div class="refsect1">
        <a id="idp123389296"></a>
        <h2>Syntax</h2>
        <pre class="synopsis">ares <span class="command"><strong>median</strong></span> asig, ksize, imaxsize [, iskip]</pre>
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      <div class="refsect1">
        <a id="idp123391456"></a>
        <h2>Initialization</h2>
        <p>
      <span class="emphasis"><em>imaxsize</em></span> -- the maximun  size of the window used to
      select the data.
      </p>
        <p>
        <span class="emphasis"><em>iskip</em></span> -- initial
        disposition of internal data space. A zero value will clear the
        space; a non-zero value will allow previous information to
        remain. The default value is 0.
      </p>
      </div>
      <div class="refsect1">
        <a id="idp123394160"></a>
        <h2>Performance</h2>
        <p>
      <span class="emphasis"><em>asig</em></span> -- input signal to be filtered
    </p>
        <p>
      <span class="emphasis"><em>ksize</em></span> -- size of the window over which the
      input is to be filtered.  It must not exceed the maximum window
      size; if it does it is truncated.
    </p>
        <p>
      <span class="emphasis"><em>median</em></span> is a simple filter that retuns the
      median value of the last <span class="emphasis"><em>ksize</em></span> values.  It
      has a lowpass action.  The efficiency decreases as the window
      size increases.
    </p>
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      <div class="refsect1">
        <a id="idp123398208"></a>
        <h2>Examples</h2>
        <p>
      Here is an example of the median opcode. It uses the file <a class="ulink" href="examples/median.csd" target="_top"><em class="citetitle">median.csd</em></a>.

      </p>
        <div class="example">
          <a id="idp123400064"></a>
          <p class="title">
            <strong>Example 483. Example of the median opcode.</strong>
          </p>
          <div class="example-contents">
            <p>See the sections <a class="link" href="UsingRealTime.html" title="Real-Time Audio"><em class="citetitle">Real-time Audio</em></a> and <a class="link" href="CommandFlags.html" title="Csound command line"><em class="citetitle">Command Line Flags</em></a> for more information on using command line flags.</p>
            <pre class="programlisting">
<span class="csdtag">&lt;CsoundSynthesizer&gt;</span>
<span class="csdtag">&lt;CsInstruments&gt;</span>
<span class="ohdr">sr</span> <span class="op">=</span> 44100
<span class="ohdr">kr</span> <span class="op">=</span> 441
<span class="ohdr">ksmps</span> <span class="op">=</span> 100
<span class="ohdr">nchnls</span> <span class="op">=</span> 1

<span class="oblock">instr</span> 1
  a1  <span class="opc">oscil</span>  30000, 10, 1
  a2  <span class="opc">median</span> a1, 5, 8
  <span class="opc">out</span> a2
<span class="oblock">endin</span>
<span class="csdtag">&lt;/CsInstruments&gt;</span>
<span class="csdtag">&lt;CsScore&gt;</span>
<span class="stamnt">f</span>1 0 4096 10 1
<span class="stamnt">i</span> 1 0 0.1 
<span class="stamnt">e</span>

<span class="csdtag">&lt;/CsScore&gt;</span>
<span class="csdtag">&lt;/CsoundSynthesizer&gt;</span>
</pre>
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        <p><br class="example-break" />
    </p>
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      <div class="refsect1">
        <a id="idp123404352"></a>
        <h2>Credits</h2>
        <p>
      </p>
        <table border="0" summary="Simple list" class="simplelist">
          <tr>
            <td>Author: John ffitch</td>
          </tr>
          <tr>
            <td>University of Bath</td>
          </tr>
          <tr>
            <td>May 2010</td>
          </tr>
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        <p>
    </p>
        <p>New in Csound version 5.13</p>
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